I got the Mirena - it was not a big deal. DH got snipped about a week after Julia was born. I was in there with him and it was not a big deal at all. They numbed it up, did a small incision and did the tube from each side. He said the incision site was sore for a while but nothing major. He had it done on a Thursday afternoon and he was back to work on Monday - and he has a very physical job.
And if DH is nervous - tell him that nothing at all has changed in our sex life!

Except maybe now we are more carefree since we now we can't get pregnant!